用LES和无限元耦合方法预报潜艇流噪声

为了系统地研究潜艇流噪声的特点,采用大涡模拟(LES)与声学无限元方法耦合,对潜艇进行频域噪声数值预报。在潜艇水动力性能及压力分布的计算后,再与试验结果对比分析,验证了水动力计算方案的准确性。在此基础上,结合声学无限元方法,对潜艇流噪声进行数值模拟,并对特征点进行频域分析。经噪声分布云图和远场特征点频谱曲线的详细分析后,可发现随着频率增加,辐射区间均会增多,而相同频率下四极子噪声辐射区间要多于偶极子。相比于面声源,体声源在总声级中的贡献度较小,可以忽略不计。由于计算的特征点总声压级与文献所提供结果吻合,验证了所采用噪声预报方法的准确性。

Prediction of Submarine Noise Based on LES and Infinite Element Method

In order to get the noise numerical prediction method of submarine, a method combined the Large Eddy Simulation (LES) with the Infinite Element Method (I-FEM) was used to predict the frequency domain noise of submarine. Hydrodynamic predictions of submarine and pressure coefficient distribution was calculated and compared with experimental data. The results show that numerical results agree well with experimental data which validated the accuracy of the numerical method. According to hydrodynamic predictions of submarine with Acoustics Infinite Element, numerical simulations for submarine flow noise and frequency domain analysis for feature points were done. It proves to be exact for prediction method comparing with previous overall sound pressure level of feature points in references. At the same time, radiation regions of dipole and quadripole are increased gradually as frequency rising, and the radiation region of quadripole is more than dipole in same frequency. Body acoustic can be neglected because whose contribution is smaller than surface acoustic in overall acoustic.